Research On Simulations And Experiments Of Magnetoelastic Biosensor

With the development of human society,human beings pay more and more attention to food safety.Dairy products are one of the indispensable drinks in people's daily life,and their safety has also obtained much attention.Staphylococcus aureus is a toxic species commonly found in dairy products,so detection of Staphylococcus aureus is imperative.Magnetoelastic biosensors are widely used in the fields of chemistry,biology,medicine,etc.due to their small size,little specimen,and convenient and fast detection process.However,there are not so many researchers doing research on the detection of Staphylococcus aureus by magnetoelastic biosensors.This paper intends to use the magnetoelastic biosensor to detect Staphylococcus aureus in milk.According to the basic principle of magnetoelastic biosensors,an improved method is proposed to improve the accuracy and sensitivity of detection.The specific contents are as follows:(1)Application research of magnetostrictive effect.Firstly,some theories the magnetostrictive effect has been studied.By analyzing the vibration mechanism of magnetostriction,the influencing factors of the resonant frequency and the detection method,it is concluded that the change of the mass load of the magnetoelastic diaphragm will cause the resonance frequency of the magnetoelastic biosensor to shift.The viscosity of the liquid in which the magnetoelastic biosensor is located also affects the resonant frequency of the magnetoelastic biosensor.This part of the research provides a basic theoretical basis for the study of magnetoelastic biosensors,and provides research ideas for finite element simulation.(2)Simulation study of magnetoelastic biosensor detection methods.The numerical analysis model of magnetoelastic sensor was established.Since the length of magnetoelastic diaphragm is an important factor affecting the fundamental frequency of magnetoelastic biosensor,the resonant frequencies of magnetoelastic sensors with different sizes are studied and explored.The results show that there are some differences between the simulation results of magnetoelastic diaphragms with different lengths and the theoretical calculations,but the trend is similar to the theoretical calculation results.The resonance frequency is inversely proportional to the length of the magnetoelastic material.(3)Magnetoelastic biosensors are used for the experimental study of Staphylococcus aureus.Based on the equipment of the laboratory,a detection system for the magnetoelastic biosensor for detecting Staphylococcus aureus was established.The detection experiment was carried out by the platform,and the resonance of the magnetoelastic biosensor and the effect of different liquid viscosity of magnetoelastic biosensors was analyzed.It also explored how magnetoelastic biosensors detect Staphylococcus aureus in milk,and the result shows that magnetoelastic biosensors respond to mass load and viscosity changes fast and using mass load changes facilitates rapid detection of S.aureus.(4)Due to some defects of the magnetoelastic biosensor in the detection of Staphylococcus aureus,an optimized method design was proposed.Considering the influence factors of the excitation signal,the change of the position of the magnetoelastic diaphragm,and exploring different sizes and magnetoelasticity.As signal obtained is very low acknowledge by the simulation analysis,the detection system should be improved to enhance signal-to-noise ratio of the signal and facilitate the detection of the response signal.The results show that the resonant frequency is higher where the sensor lays on the side of coil.It is better to obtain a high sensitivity.Besides,the stability of the sensor is also improved when the sensor was fixed.